I have compiled 1.6_BETA1 today.
the source is checked out  as 
  cvs co -r netbsd-1-6 src
build is done on the machine 20020407-1.5ZC,

It was very simple:

cvs -d :pserver:anoncvs@anoncvs.netbsd.org:/cvsroot checkout -r netbsd-1-6 src
./build.sh -R /export/netbsd-1-6-r -D /export/netbsd-1-6-d >& ../netbsd-1-6-build.sh-20020526

The binaries are placed on
 ftp://ftp.ki.nu/pub/NetBSD/arch/macppc/snapshot/20020526-1.6_BETA/

I have tested this binary on StarMax 3000/240 from installation,

run sysinst from boot.fs,
(1) There is nfs fallback problem PR bin/15469
    http://www.netbsd.org/cgi-bin/query-pr-single.pl?number=15469

    nfs install may not be done from regular NetBSD/macppc server,
    unless you manunally mount by 
      mount_nfs -2 server:/binaries /nfs
    So I took ftp install.

(2) installboot has a problem, as,

 Status: Failed: command failed
    Command: /usr/sbin/installboot /dev/rwd0a /usr/mdec/bootxx /boot
     Press any key to continue
--------------------------------------------------------------------
sysinst: execvp /usr/sbin/installboot: No such file or directory

(3) Alternative, trying recent macppc.fs I've got

 Status: Failed: command failed
    Command: /usr/mdec/installboot /mnt/boot /usr/mdec/bootxx /dev/rwd0a
     Press any key to continue
---------------------------------------------------------------------
installboot: nlist: /usr/mdec/bootxx: symbols not found

(4) So by using  boot.fs from 20020407-1.5ZC: boot.fs 
installboot is done manually.

  # cd /usr/mdec
  # ./installboot -v /mnt/boot bootxx /dev/rwd0a


Is binary by AutoBuild stuff public accessible ?
http://releng.netbsd.org/ab/M_macppc/
---
Makoto Fujiwara, 
Chiba, Japan, Narita Airport and Disneyland prefecture.